/*******************************************************************************
 * Copyright (c) 2009, 2021 Mountainminds GmbH & Co. KG and Contributors
 * This program and the accompanying materials are made available under
 * the terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *    Marc R. Hoffmann - initial API and implementation
 *
 *******************************************************************************/
package org.jacoco.report;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;

import java.io.IOException;
import java.io.Reader;
import java.util.HashMap;
import java.util.Map;

import org.junit.Before;
import org.junit.Test;

/**
 * Unit tests for {@link MultiSourceFileLocator}.
 */
public class MultiSourceFileLocatorTest {

	private MultiSourceFileLocator locator;

	@Before
	public void setup() {
		locator = new MultiSourceFileLocator(7);
	}

	@Test
	public void testGetTabWidth() throws IOException {
		assertEquals(7, locator.getTabWidth());
	}

	@Test
	public void testEmpty() throws IOException {
		assertNull(locator.getSourceFile("org/jacoco/example", "Test.java"));
	}

	@Test
	public void testNohit() throws IOException {
		final StubLocator loc1 = new StubLocator();
		locator.add(loc1);
		final StubLocator loc2 = new StubLocator();
		locator.add(loc2);
		final StubLocator loc3 = new StubLocator();
		locator.add(loc3);

		assertNull(locator.getSourceFile("org/jacoco/example", "Test.java"));
	}

	@Test
	public void testHit() throws IOException {
		final StubLocator loc1 = new StubLocator();
		loc1.put("org/jacoco/example/Test1.java", '1');
		locator.add(loc1);
		final StubLocator loc2 = new StubLocator();
		loc2.put("org/jacoco/example/Test2.java", '2');
		locator.add(loc2);
		final StubLocator loc3 = new StubLocator();
		loc3.put("org/jacoco/example/Test3.java", '3');
		locator.add(loc3);

		final Reader source = locator.getSourceFile("org/jacoco/example",
				"Test2.java");
		assertNotNull(source);
		assertEquals('2', source.read());
	}

	@Test
	public void testPrecedence() throws IOException {
		final StubLocator loc1 = new StubLocator();
		loc1.put("org/jacoco/example/TestX.java", '1');
		locator.add(loc1);
		final StubLocator loc2 = new StubLocator();
		loc2.put("org/jacoco/example/Test.java", '2');
		locator.add(loc2);
		final StubLocator loc3 = new StubLocator();
		loc3.put("org/jacoco/example/Test.java", '3');
		locator.add(loc3);

		final Reader source = locator.getSourceFile("org/jacoco/example",
				"Test.java");
		assertNotNull(source);
		assertEquals('2', source.read());
	}

	private static class StubLocator implements ISourceFileLocator {

		private final Map<String, Reader> sources = new HashMap<String, Reader>();

		void put(String path, char content) {
			sources.put(path, new StubReader(content));
		}

		public Reader getSourceFile(String packageName, String fileName)
				throws IOException {
			return sources.get(packageName + "/" + fileName);
		}

		public int getTabWidth() {
			return 0;
		}
	}

	private static class StubReader extends Reader {

		private final char content;

		StubReader(char content) {
			this.content = content;
		}

		@Override
		public int read(char[] cbuf, int off, int len) throws IOException {
			for (int idx = 0; idx < len; idx++) {
				cbuf[off + idx] = content;
			}
			return len;
		}

		@Override
		public void close() throws IOException {
		}

	}

}
